I also saw May 26 opening and it's posted at https://www.nps.gov/yose/planyourvisit/tioga.htm
Seems very arbitrary. It not likely that they are working on the road Saturday and Sunday of a three-day weekend, so road is probably ready to go. Is it because of staffing availability or that staff wants to open it on a holiday so they get overtime?

I think I'm the only one who did not pick a date before Memorial Day weekend. But I picked the Wednesday after, not the holiday thinking they may need one more day after holiday to may sure 120 is OK for opening. So I could 'win' my second consecutive 'darn close'.

I'm also the only one in contest who may be using Tioga in the next week. My original plan was to drive to and ski Palisades on their closing day, Memorial Day, then stay at South Lake Tahoe family cabin Monday night. That breaks up drive to Mammoth. Then I planned to drive to Mammoth early on Tuesday, ski and stay there Tuesday, ski Mammoth Wednesday, then drive home over Sonora Pass after skiing to be home for dental appt. on Thursday. But friend I stay with at Mammoth reminded me that Palisades does not appear to make much effort to provide their best product for customers at end of the season and Mammoth gondola closes for annual maintenance after Memorial Day, so I'd be better off skiing Pailsades Sunday and Mammoth Monday and Tuesday.

But a fire has the usual route from Reno/Tahoe/Minden past Mono Lake closed and the alternative adds 2+ hours which makes it difficult to drive it before skiing. Note that Mammoth is open 730 AM - 2 PM at this time of year and best skiing may be before noon so a 4+ hr drive from Minden to avoid 395 closure is not very practical. https://www.sfgate.com/bayarea/artic...n-20343034.php